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Howlett" , Linus Torvalds , linux-arm-kernel@axis.com, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-ide@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mips@vger.kernel.org, linux-mmc@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, Marco Elver , Marek Szyprowski , Michal Hocko , Mike Rapoport , Muchun Song , netdev@vger.kernel.org, Oscar Salvador , Peter Xu , Robin Murphy , Suren Baghdasaryan , Tejun Heo , virtualization@lists.linux.dev, Vlastimil Babka , wireguard@lists.zx2c4.com, x86@kernel.org References: <20250827220141.262669-1-david@redhat.com> <20250827220141.262669-11-david@redhat.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZoEEwEIAEQCGwMCF4ACGQEFCwkIBwICIgIG FQoJCAsCBBYCAwECHgcWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaJzangUJJlgIpAAKCRBN 3hD3AP+DWhAxD/9wcL0A+2rtaAmutaKTfxhTP0b4AAp1r/eLxjrbfbCCmh4pqzBhmSX/4z11 opn2KqcOsueRF1t2ENLOWzQu3Roiny2HOU7DajqB4dm1BVMaXQya5ae2ghzlJN9SIoopTWlR 0Af3hPj5E2PYvQhlcqeoehKlBo9rROJv/rjmr2x0yOM8qeTroH/ZzNlCtJ56AsE6Tvl+r7cW 3x7/Jq5WvWeudKrhFh7/yQ7eRvHCjd9bBrZTlgAfiHmX9AnCCPRPpNGNedV9Yty2Jnxhfmbv Pw37LA/jef8zlCDyUh2KCU1xVEOWqg15o1RtTyGV1nXV2O/mfuQJud5vIgzBvHhypc3p6VZJ lEf8YmT+Ol5P7SfCs5/uGdWUYQEMqOlg6w9R4Pe8d+mk8KGvfE9/zTwGg0nRgKqlQXrWRERv cuEwQbridlPAoQHrFWtwpgYMXx2TaZ3sihcIPo9uU5eBs0rf4mOERY75SK+Ekayv2ucTfjxr Kf014py2aoRJHuvy85ee/zIyLmve5hngZTTe3Wg3TInT9UTFzTPhItam6dZ1xqdTGHZYGU0O otRHcwLGt470grdiob6PfVTXoHlBvkWRadMhSuG4RORCDpq89vu5QralFNIf3EysNohoFy2A LYg2/D53xbU/aa4DDzBb5b1Rkg/udO1gZocVQWrDh6I2K3+cCs7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: hNA1Zv64YB4-TexC2MioOHJ6o5ODFRqB-1TqJOjHS-s_1756462234 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 6818A2000F X-Stat-Signature: oqhx8zxgwk835djtcquek7x5mz8ueyd1 X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1756462237-609283 X-HE-Meta: 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 7vBejPSo W7vdUTd6OmqD02mVGXQozf1cEzcTrKf4zhMnHmBeni7Fl4dAhUZc4vgKIqoFSooQhueORlkjB6Rxuix9gz6f8jpY0Cc458in+zXO4BaX5ACm/1Ebixii236Wds3OjxpqNROJUZuPO6g1zEAS4hsf8Lo0kbXVrtZCv1P5GuEc8cnR7+tl0eOL7212wmlbwbbgSWi843bicfrUKqFXMwBxu3oA4kVPGocLrIFoB5+beMy2FOSPjdhMQoLZ7z7XpGzUiVFAlBMCvNuq1Py0lh3TLnOwAWgfRa+mNb3Zv62cNeS0OXOQiprcs1A1Q2UVACSuTeBFXKjcWWDsCMO3gLYuVOrgUOM3fBQB4gN+s7pZ7VC56UgTjnwk2pAB0eRBY9MT0aK06NucJT/fNUgSqvpdOCu3N4S9zewZEyNWgLgtM3pCoi+45bJ8Axp1mNS5pojPQ7Upb5i+XSa4wll0WzwexwALt20rovlhRIBUZtgz0ip1RfrD15F4U43dMdjzle7NwZebF X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 28.08.25 17:00, Lorenzo Stoakes wrote: > On Thu, Aug 28, 2025 at 12:01:14AM +0200, David Hildenbrand wrote: >> Let's sanity-check in folio_set_order() whether we would be trying to >> create a folio with an order that would make it exceed MAX_FOLIO_ORDER. >> >> This will enable the check whenever a folio/compound page is initialized >> through prepare_compound_head() / prepare_compound_page(). > > NIT: with CONFIG_DEBUG_VM set :) Yes, will add that. > >> >> Reviewed-by: Zi Yan >> Signed-off-by: David Hildenbrand > > LGTM (apart from nit below), so: > > Reviewed-by: Lorenzo Stoakes > >> --- >> mm/internal.h | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/mm/internal.h b/mm/internal.h >> index 45da9ff5694f6..9b0129531d004 100644 >> --- a/mm/internal.h >> +++ b/mm/internal.h >> @@ -755,6 +755,7 @@ static inline void folio_set_order(struct folio *folio, unsigned int order) >> { >> if (WARN_ON_ONCE(!order || !folio_test_large(folio))) >> return; >> + VM_WARN_ON_ONCE(order > MAX_FOLIO_ORDER); > > Given we have 'full-fat' WARN_ON*()'s above, maybe worth making this one too? The idea is that if you reach this point here, previous such checks I added failed. So this is the safety net, and for that VM_WARN_ON_ONCE() is sufficient. I think we should rather convert the WARN_ON_ONCE to VM_WARN_ON_ONCE() at some point, because no sane code should ever trigger that. -- Cheers David / dhildenb